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When to Plant Tatsoi in Polk County, OR

Tatsoi is a compact Asian green forming beautiful rosettes of dark, spoon-shaped leaves with a mild mustard flavor. It is extremely cold-hardy and versatile.

Polk County, Oregon is in USDA Zone 8a. The average last spring frost is April 10 and the first fall frost is October 31, giving you a growing season of approximately 204 days.

At an elevation of 331 feet, Polk County receives approximately 54.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81ยฐF, so choose short-season varieties of Tatsoi to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Tatsoi root diseases.

Polk County, OR (Zone 8a) Long season
204 days
Last Spring Frost April 10
204 growing days
First Fall Frost October 31

Polk County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (145 days to spare)
Start indoors: Feb 17 Transplant: Mar 24 🍅 Harvest: Apr 28 – Jun 2
Recommended (50%) ✓ Fits season (134 days to spare)
Start indoors: Mar 6 Transplant: Apr 10 🍅 Harvest: May 15 – Jun 19
Safe Start (90%) ✓ Fits season (140 days to spare)
Start indoors: Mar 28 Transplant: May 2 🍅 Harvest: Jun 6 – Jul 11

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Polk County

How your county's soil matches Tatsoi's growing requirements.

Soil pH

Your soil pH (5.7โ€“6.5) overlaps with Tatsoi's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in Polk County is excellent for Tatsoi โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.7%) โ€” Tatsoi will thrive.

How to Plant Tatsoi

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Tatsoi

7
successive plantings in your 204-day season

Sow every 4 weeks. Last sowing by Sep 11 to harvest before frost.

For a dedicated fall crop, sow by Aug 22.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Tatsoi

Tatsoi needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Tatsoi Needs Rainfall You Supplement Action
Jan โ€” 8.7" 0" โ„๏ธ Dormant
Feb โ€” 5.6" 0" โ„๏ธ Dormant
Mar โ€” 5" 0" โ„๏ธ Dormant
Apr 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
May 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Jun 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Jul 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Aug 4.3" 1.1" 3.2" ๐Ÿšฟ Regular watering
Sep 4.3" 1.8" 2.5" ๐Ÿšฟ Regular watering
Oct 4.3" 4.5" 0" โœ… Rainfall sufficient
Nov โ€” 8.1" 0" โ„๏ธ Dormant
Dec โ€” 8.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Polk County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Tatsoi Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Tatsoi needs ~457 GDD — county provides 2,193 GDD Excellent fit

Tatsoi Planting Timeline โ€” Polk County, OR

Tatsoi Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 โ€“ Mar 20
Transplant Outdoors April 10 Apr 10 โ€“ Apr 24
Direct Sow March 27 Mar 27 โ€“ Apr 17
Harvest May 15 May 15 โ€“ Jun 19
Fall Sowing August 22 Aug 22 โ€“ Sep 5

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July โ€”
August Fall Sowing
September Fall Sowing
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

35โ€“50 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

204 days in Polk County

Growing Tips for Tatsoi in Polk County

Direct sow Tatsoi outdoors after April 10 in Polk County when soil has warmed and frost danger has passed.

Your generous 204.0-day season in Polk County allows multiple plantings of Tatsoi. Sow every 17.0 days for continuous harvest.

Common pests for Tatsoi in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring or fall. Tatsoi tolerates frost down to 15F. Harvest outer leaves or cut whole rosettes. Excellent in salads, stir-fries, or lightly wilted.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Tatsoi in Polk County, OR?

Polk County is in Zone 8a with an average last frost of April 10. Plan your Tatsoi planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Polk County, OR?

Polk County, Oregon is in USDA Hardiness Zone 8a. The average last spring frost is April 10 and first fall frost is October 31.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Polk County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Polk County, OR. Local conditions may vary. Last updated: April 2026.